Magical animals of white colour were common in Celtic and Welsh mythology. The legends of King Arthur include a story about the pursuit of a large, white deer, leading to the arrival at the magical Sir Pellinore's well.[2]

Douglas A. Anderson has noted that the appearance of white deer in The Hobbit forebodes the approach by Bilbo and company to the Wood-elven area of Mirkwood, as "[i]n Celtic tradition, encounters with white animals (especially white deer) usually prefigure an encounter with beings from the Otherworld (Faërie)".[3]

The White Hart is the largest breed of deer found in northwestern Middle-earth (rumoured to have Faerie blood). The suggested Sindarin name of this type of deer was Nimfiara in the early publications from MERP, later revised to Nimmerais (sing. Nimmaras).[4][5]